Peripheral devices (PDs) allow users to interact with a computer. Examples of PDs include keyboards, mice, game controls, joysticks, digitizing pads, etc. PDs are often connected to a computer though an interface called Universal Serial Bus (USB).
USB is a generic computer interface that can connect a multitude of PDs to a single USB port on a computer. A USB equipped computer will auto-detect and auto-configure a PD that is plugged into a USB port. Two versions of USB currently exist. The first version is referred to as USB 1.1, and the second version is referred to as USB 2.0. The specifications for both versions are widely available on the Internet and elsewhere.
USB auto-detection and auto-configuration relies on report descriptors. Report descriptors are stored in USB PDs, and they identify the PD device to the computer operating system. The report descriptors are typically relatively long in order to accommodate as many types of devices as possible.
A conventional computer system may take advantage of wireless technologies for connecting to PDs. IEEE 802.11 “WiFi” and Bluetooth are two popular wireless technologies being used for this purpose. A wireless system will typically use a wireless-to-USB bridge to enable the computer to receive and transmit data with the PD wirelessly. The bridge is generally responsible for communicating with the wireless USB devices and it obtains the report descriptors from the PD and, in turn, sends the report descriptors to the computer.
Many wireless devices are very power sensitive since they run on batteries and power is used every time a wireless transmission occurs. One factor that determines the amount of power required to transmit a report descriptor is the length of the report descriptor. Additionally, the amount of memory required to store a report descriptor in a PD depends on the length of the report descriptor.